Thursday Night Update from Meteorologist Scot Pilie — Growing risk for heavy rainfall, coastal flooding, and some wind impacts across the Gulf Coast this weekend from Cristobal.
The 10PM National Hurricane Center now has the system moving east at 3mph, indicating the long-awaited northerly turn is likely to begin soon. Landfall still expected near Terrebonne/St Mary Parish, with most of the impacts along and EAST of where the center comes ashore.
Tropical storm and storm surge watches likely to be issued by Friday.
Remember, a Storm Surge Watch & Tropical Storm Watch is issued 48 hours in advance of potential impacts of coastal flooding and tropical-storm force winds(39mph). That would mean impacts as early as late Saturday night-Sunday morning.
National Hurricane Center mentions, “There is a risk of tropical storm force winds this weekend from Louisiana to the western Florida Panhandle and a risk of dangerous storm surge from Louisiana to the Florida Big Bend.”
Once Cristobal emerges into the Gulf of Mexico, it will be a BROAD, lopsided tropical storm. Even if the system only strengthens to a moderate/strong tropical storm, the impacts will extend far away from landfall.
Notice the purple in the graphic above? That’s the tropical-storm force wind gusts(39+mph) extending 300-400 miles east of the center!
Most of the impacts(coastal flooding, tropical storm force winds, and rainfall) will extend way east of the center of circulation. So, if the system passes east of you…you might find yourself with little impact at all!
The takeaway point? Don’t focus solely on the “cone of uncertainty” the next few days, as the rough weather could extend outside of the cone, potentially hundred of miles away from the center.
Impacts for south Louisiana could begin as early as overnight Saturday with potential landfall late Sunday-early Monday. Sunday-Monday would be the primary impact days.
Heavy rainfall and coastal flooding of 2-4 feet outside of levee protection will be the primary concerns.
FLASH FLOOD WATCH — Remains in effect from now until 7AM Tuesday. 4-6 inches of rainfall likely, with localized 10” rainfall amounts.
Can’t stress this enough, these projected amounts will change drastically depending on the track & organization of Cristobal.
In addition, some wind impacts will be possible with sporadic power outages Sunday-Monday.
With lopsided systems like Cristobal…it’s often a wait & see game. Where does the system track? Where do the heaviest rain bands set up? How much dry air does the system encounter?
Lot’s of details still to be ironed out with this one! Stay tuned.
Clear out your storm drains, pick up loose items around the yard, and prepare just in case!